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Journal of Materials Science & Technology 2021年第36期95卷 145-157页

作者： S.Samat M.Z.Omar A.H.Baghdadi i.f.mohamed A.Rajabi A.M.Aziz Department of Mechanical and Manufacturing Engineering Faculty of Engineering and Built EnvironmentUniversiti Kebangsaan MalaysiaBangiUKM 43600Malaysia

Al–Si–Cu–Mg foundry alloys are used in casting process ***,their strength properties remain low due to their microstructural characteristics and *** this work,the microstructural characteristics,dislocation densities,and mechanical properties of Al–Si–Cu–Mg cast alloys prepared through different casting methods were studied *** casting processes,namely,gravity casting(GC),rheocasting(RC),thixoforming(Thixo),and Thixo with heat treatment,were *** GC and RC samples had mainly dendriticα-Al phase microstructures and exhibited coarse Si particles and intermetallic compounds in their interdendritic *** contrast,the Thixo and heat-treated Thixo(HT-Thixo)samples exhibited microstructural refinement with uniformly distributedα-Al globules,fine fibrous Si particles,and fragmented intermetallic compounds amongα-Al *** accumulation of dislocation densities increased in the Thixo sample as the strain was increased due to plastic ***,the ultimate tensile strength and yield strength of the HT-Thixo sample increased by 87%and 63%,respectively,relative to those of the GC *** cleavage fracture displayed by the GC and RC samples led to brittle ***,the Thixo and HT-Thixo samples presented dimple-based ductile fracture.

关键词： Al–Si–Cu–Mg alloy Thixoforming Microstructure Mechanical property Dislocation density

Adsorption of U(Ⅵ) from acid solution on a low-cost sorbent:equilibrium, kinetic, and thermodynamic assessments

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Nuclear Science and Techniques 2019年第10期30卷 105-122页

作者： mohamed f.Cheira Hamed i.Mira Ahmed K.Sakr Saad A.mohamed Nuclear Materials Authority P.O.Box 530MaadiCairoEgypt Chemistry Department Faculty of ScienceAin Shams UniversityCairoEgypt

in this paper,waste clay was cured with ethyl acetate to obtain treated clay(TC),which was modified with gallic acid to obtain a low-cost sorbent that was characterized by EDX,SEM,and fTiR ***(Ⅵ)adsorption was achieved using the batch adsorption method on the TC and gallic acid-modified treated clay(GMTC).The maximum uptakes of U(Ⅵ)on TC and GMTC were 37.2 and 193.0 mg/g,*** U(Ⅵ)adsorption kinetics on the TC and GMTC sorbents were well-fitted by the pseudo-second-order mechanism,and the adsorption equilibrium followed the Langmuir *** optimum parameters were applied to El Sela leach solution for uranium recovery.

关键词： Waste clay Gallic acid Modification Uranium adsorption Equilibrium kinetics

Study of micro-elongated thermoelastic medium loaded with a piezoelectric layer under the influence of gravity using the dual-phase-lag model

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international Journal of Mechanical System Dynamics 2023年第2期3卷 136-145页

作者： mohamed i.A.Othman Ebtesam E.M.Eraki mohamed f.ismail Department of Mathematics Faculty of ScienceZagazig UniversityZagazigEgypt Department of Engineering Mathematics and Physics Higher Institute of EngineeringShorouk AcademyAl-Shorouk CityEgypt

This paper aims to examine the influence of gravity on a thermoelastic microelongated layer when a piezoelectric layer is above it,utilizing the theory of Lord–Shulman(L–S)and also the model of dual‐phase‐lag(DPL).A partial differential equation was transformed into an ordinary differential equation using the normal mode *** epoxy numerical computations are carried out,and the results are presented in graphical *** L–S theory and the model of DPL are compared in the presence and absence of gravity and it is found that gravity has quite a massive influence on all the physical quantities.

关键词： piezoelectrics normal mode analysis gravity micro‐elongated thermoelastic DPL model

Numerical Study of flow and Gas Diffusion in the Near-Wake behind an isolated Building

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Advances in Atmospheric Sciences 2009年第6期26卷 1241-1252页

作者： mohamed f.YASSiN Department of Environmental Technology Management College for WomenKuwait University P.O.Box 5969KuwaitSafat 13060Kuwait faculty of Engineering Assiut UniversityAssiut-71516Egypt

To assist validation of the experimental data of urban pollution dispersion, the effect of an isolated building on the flow and gaseous diffusion in the wake region have been investigated numerically in the neutrally stratified rough-walled turbulent boundary layer. Numerical studies were carried out using Computational fluid Dynamics （CfD） models. The CfD models used for the simulation were based on the steady-state Reynolds-Average Navier-Stoke equations （RANS） with κ-ε turbulence models; standard κ-ε and RNG κ-ε models. inlet conditions and boundary conditions were specified numerically to the best information available for each fluid modeling simulation. A gas pollutant was emitted from a point source within the recirculation cavity behind the building model. The accuracy of these simulations was examined by comparing the predicted results with wind tunnel experimental data. it was confirmed that simulation using the model accurately reproduces the velocity and concentration diffusion fields with a fine-mish resolution in the near wake region. Results indicated that there is a good agreement between the numerical simulation and the wind tunnel experiment for both wind flow and concentration diffusion. The results of this work can help to improve the understanding of mechanisms of and simulation of pollutant transport in an urban environment.

关键词： atmospheric turbulence CfD model isolated building pollutant dispersion

impact of composition ratio on the structure and optical properties of(1-x)Mnfe_(2)O_4/(x)ZnMn_(2)O_4 nanocomposite

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Chinese Physics B 2022年第7期31卷 481-489页

作者： Zein K.Heiba mohamed Bakr mohamed Ali A.Alkathiri Sameh i.Ahmed A A Alhazime Department of Physics Faculty of ScienceAin shams UniversityCairo 11566Egypt Physics Department Faculty of ScienceTaibah UniversityAl-Madina al MunawarahSaudi Arabia Depatment of Physics College of ScienceTaif UniversityP.O.Box 11099Taif 21944Saudi Arabia

(1-x)Mnfe_(2)O_(4)(MfO)/xZnMn_(2)O_(4)(ZMO)(x=0,0.2,0.5,0.8,and 1.0)nanocomposite samples were prepared using co-precipitation *** phase percentage,cell parameters,and crystallite size of MfO and ZMO phases in each nanocomposite sample were calculated using Rietveld refinement *** x-ray diffraction(XRD)analysis and fourier-transform infrared spectroscopy techniques established the variation in the lattice parameters of each phase are due to permutation of all cations among the octahedral and tetrahedral sites of MfO and *** different oxidation states of different ions in all samples were determined using x-ray photoelectron spectroscopy(XPS)*** variation in absorbance of the nanocomposite samples with composition parameter(x)is dependent on the wavelength *** optical bandgap of the nanocomposite samples is decreased as the content of ZMO phase *** effect of alloying on the refractive index,extinction coefficient,dielectric constant,optical conductivity,and the nonlinear optical behaviors of all samples were studied in *** nanocomposite sample x=0.5 disclosed upgraded optical parameters with the highest refractive index,optical conductivity,and PL intensity,which nominate it to be functional in various application fields.

关键词： MfO and ZMO composite XPS structure optical

Photovoltaic Models Parameters Estimation Based on Weighted Mean of Vectors

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Computers, Materials & Continua 2023年第3期74卷 5229-5250页

作者： mohamed Elnagi Salah Kamel Abdelhady Ramadan mohamed f.Elnaggar Department of Electrical Engineering Faculty of EngineeringAl-Azhar UniversityQena83518Egypt Department of Electrical Engineering Faculty of EngineeringAswan UniversityAswan81542Egypt Department of Electrical Engineering College of EngineeringPrince Sattam Bin Abdulaziz UniversityAl-Kharj11942Saudi Arabia Department of Electrical Power and Machines Engineering Faculty of EngineeringHelwan UniversityHelwan11795Egypt

Renewable energy sources are gaining popularity,particularly photovoltaic energy as a clean energy *** is evident in the advancement of scientific research aimed at improving solar cell *** to the non-linear nature of the photovoltaic cell,modeling solar cells and extracting their parameters is one of the most important challenges in this *** a result,the use of optimization algorithms to solve this problem is expanding and evolving at a rapid *** this paper,a weighted meaN of vectOrs algorithm(iNfO)that calculates the weighted mean for a set of vectors in the search space has been applied to estimate the parameters of solar cells in an efficient and precise *** each generation,the iNfO utilizes three operations to update the vectors’locations:updating rules,vector merging,and local *** iNfO is applied to estimate the parameters of static models such as single and double diodes,as well as dynamic models such as integral and fractional *** outcomes of all applications are examined and compared to several recent *** well as the results are evaluated through statistical *** results analyzed supported the proposed algorithm’s efficiency,accuracy,and durability when compared to recent optimization algorithms.

关键词： Photovoltaic(PV)modules weighted meaN of vectOrs algorithm(iNfO) renewable energy static PV models dynamic PV models solar energy

Radioactivity and mineralogy of the altered granites of the Wadi Ghadir shear zone, South Eastern Desert, Egypt

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Chinese Journal Of Geochemistry 2012年第1期31卷 30-40页

作者： mohamed f.Raslan mohamed G.El-feky Nuclear Materials Authority El Maadi P.O.Box 530CairoEgypt

Quartz-diorite, gneissose granodiorites, two-mica granite and perthite leucogranie are the main rock units cropping out in the Wadi Ghadir area, South Eastern Desert of Egypt. Along the NNE-SSW mega-faults, a broad brittle shear zone is developed in the Ghadir two-mica granite. Brittle deformation is manifested by severe myloniti-zation and alteration of these granites. These sheared altered granites are characterized by the presence of radioactive mineralization, associated with alteration features such as silicification, hematization and kaolinitization. Radioelement measurements revealed that the unaltered and altered two-mica granites are considered as uraniferous granites. The average uranium and thorium contents in the unaltered two-mica granites are 12.29×10-6 and 19.81×10-6, respectively, and the average Th/U ratio is 1.62. The altered granites exhibit higher concentrations of U (averaging 97.949), but have lower Th and Th/U ratios (13.83 and 0.16, respectively), which indicates uranium enrichment in the granites. Binary relations of eTh/eU against either eU or eTh and eU with eTh in the studied gran-ites suggest that the distribution of radioactive elements not only magmatic (positive correlation between eU and eTh), but also due to hydrothermal redistribution of radioelements (weak correlation between eU and eTh/eU). The magmatic U and Th are indicated by the presence of uraninite, thorite, zircon and monazite whereas the evidence of hydrothermal mineralization is the alteration of rock-forming minerals such as feldspar and the forma-tion of secondary minerals such as uranophane and pyrite. Microscopic, XRD and scanning electron microscopic studies revealed the presence of uraninite, uranophane, thorite, Ce-monazite and zircon, in addition to phlogopite-fluor mica in the studied altered granites of the Wadi Ghadir shear zone.

关键词：二云母花岗岩放射性元素脆性剪切带蚀变特征矿物学沙漠埃及扫描电子显微镜

insights into the adsorption performance and mechanism of Cr(Ⅵ)onto porous nanocomposite prepared from gossans and modified coal interface:Steric,energetic,and thermodynamic parameters interpretations

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Chinese Journal of Chemical Engineering 2023年第9期61卷 118-128页

作者： mohamed Mobarak Saleh Qaysi mohamed Saad Ahmed Yasser f.Salama Ahmed mohamed Abbass mohamed Abd Elrahman Hamdy AAbdel-Gawwad Moaaz K.Seliem Physics Department Faculty of ScienceBeni-Suef UniversityEgypt Geology and Geophysics Department College of ScienceKing Saud University11451 RiyadhSaudi Arabia Geology Department Faculty of ScienceBeni-Suef UniversityEgypt Department of Building Materials and Construction ChemistryInstitute of Civil EngineeringTechnische Universitat BerlinBerlinGermany Structural Engineering Department Faculty of EngineeringMansoura UniversityMansouraEgypt Raw Building Materials and Processing Technology Research institute Housing and Building National Research Center(HBRC)CairoEgypt faculty of Earth Science Beni–Suef UniversityEgypt

Herein,iron oxide/hydroxides deposits(gossans)were utilized,for the first time,in the fabrication of magnetite nanoparticles(MNPs)to load modified coal(MC).The as-synthesized MNPs@MC composite was characterized via different techniques and utilized for the Cr(Ⅵ)*** studies supported by theoretical treatment were applied to offer a new overview of the Cr(Ⅵ)adsorption geometry and mechanism at 25-45℃.Experimental results suggested that the Cr(Ⅵ)uptake was mainly governed by adsorption-reduction coupled *** Langmuir model fitted well the Cr(Ⅵ)adsorption data with maximum adsorption capacities extended from 115.24 to 129.63 mg·g^(-1).Theoretical calculations indicated that Cr(Ⅵ)ions were adsorbed on the MNPs@MC following the theory of the advanced monolayer statistical *** number of ions removed per site ranged from 1.88 to1.23 suggesting the involvement of vertical geometry and multi-ionic mechanism at all *** increment of the active sites density and the adsorption capacity at saturation with improving temperature reflected an endothermic ***,the Cr(Ⅵ)adsorption was controlled by physical forces as the adsorption energies were less than 40 kJ·mol^(-1).The calculated free enthalpy,*** internal energy explained the spontaneous nature and the viability of Cr(Ⅵ)adsorption on the MNPs@MC *** results offer a new approach in utilizing the iron-rich deposits as gossans in the preparation of magnetic and low-cost adsorbents for wastewater remediation.

关键词： Coal Magnetic nanoparticles Cr(Ⅵ)adsorption Statistical models Thermodynamic parameters

Mineralogy and radioactivity of pegmatites from South Wadi Khuda area,Eastern Desert,Egypt

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Chinese Journal Of Geochemistry 2010年第4期29卷 343-354页

作者： mohamed f.Raslan mohamed A.Ali mohamed G.El-feky Nuclear Materials Authority P.O.Box 530El MaadiCairoEgypt

Radioactive minerals in pegmatites associated with granitic rocks are commonly encountered in the south of the Wadi Khuda area and found as dyke-like and small *** are observed within garnet-muscovite granites near the contact with older *** surveys indicated that the studied pegmatites vary in dimensions ranging from 2 to 10 m in width and from 10 to 500 m in *** are composed mainly of intergrowth of milky quartz,reddish-pink K-feldspar and plagioclase together with small pockets of *** radiometric measurements indicated that radioactivity in pegmatites is more than twice that of their enclosing country *** measurements revealed that the average contents of U and Th increase gradually from rocks of dioritic to granodioritic composition(1.5×10-6 U and 4.3×10-6 Th) and increase significantly in biotite granites(5.8×10-6 U and 15.2×10-6 Th) but drastically decrease in muscovite granites(2.2×10-6 U and 5.6×10-6 Th).The average contents of U and Th of anomalous pegmatites are 95.3×10-6 and 116.9×10-6,respectively,indicating their uraniferous *** the south of the Wadi Khuda area,pegmatites are low in average Th/U(1.4) and high in average U/K(35.6),which suggests that uranium concentrating processes did not affect the pegmatites,indicating poor *** investigations of the studied pegmatites revealed the presence of secondary uranium minerals(kasolite and autunite),in addition to zircon,thorite,apatite,garnet and *** and secondary radioactive mineralizations indicated that the mineralization is not only magmatic,but also *** microprobe analyses showed distinct cryptic chemical zoning within thorite where UO2 decreases from core to *** feature in thorite is sporadic,suggesting non-uniform redistributions of UO2 within thorite during magmatic processes.

关键词：放射性核素伟晶岩矿物学黑云母花岗岩平均含量沙漠埃及电子探针分析

Small heat shock protein B8:from cell functions to its involvement in diseases and potential therapeutic applications

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Neural Regeneration Research 2025年第10期20卷 2872-2886页

作者： Marta Chierichetti Riccardo Cristofani Valeria Crippa Veronica ferrari Marta Cozzi Elena Casarotto Paola Pramaggiore Laura Cornaggia Guglielmo Patelli Ali mohamed Margherita Piccolella Mariarita Galbiati Paola Rusmini Barbara Tedesco Angelo Poletti Laboratory of Experimental Biology Dipartimento di Scienze Farmacologiche e Biomolecolari“Rodolfo Paoletti”(DiSFeB)Universitàdegli Studi di MilanoMilanItaly

Heat shock protein family B(small)member 8(HSPB8)is a 22 kDa ubiquitously expressed protein belonging to the family of small heat shock ***8 is involved in various cellular mechanisms mainly related to proteotoxic stress response and in other processes such as inflammation,cell division,and ***8 binds misfolded clients to prevent their aggregation by assisting protein refolding or degradation through chaperone-assisted selective *** line with this function,the pro-degradative activity of HSPB8 has been found protective in several neurodegenerative and neuromuscular diseases characterized by protein misfolding and *** cancer,HSPB8 has a dual role being capable of exerting either a pro-or an anti-tumoral activity depending on the pathways and factors expressed by the model of cancer under ***,HSPB8 exerts a protective function in different diseases by modulating the inflammatory response,which characterizes not only neurodegenerative diseases,but also other chronic or acute conditions affecting the nervous system,such as multiple sclerosis and intracerebellar *** note,HSPB8 modulation may represent a therapeutic approach in other neurological conditions that develop as a secondary consequence of other *** is the case of cognitive impairment related to diabetes mellitus,in which HSPB8 exerts a protective activity by assuring mitochondrial *** review aims to summarize the diverse and multiple functions of HSPB8 in different pathological conditions,focusing on the beneficial effects of its ***-based and alternative therapeutic approaches targeting HSPB8 and its regulated pathways will be discussed,emphasizing how new strategies for cell and tissue-specific delivery represent an avenue to advance in disease treatments.

关键词： aggregation autophagy cancer chaperone chaperone-assisted selective autophagy cognitive impairment HSPB8 neuroinflammation neuromuscular diseases therapy